Telegraph system



oct. 2; 1945',

START SHIFT G COMBINATION ODE FIG. 5

STOP

L. M. POTTS TELEGRAPH SYSTEM 2 sheets-sheet 24 I original Filed oci.2o,V 1941 nRECEIVING STATION INVEN Ton I Louls M. PoTrs Patented Oct. 2,1945 IIlELEGrRAI-H SYSTEM Louis M. Potts, Evanston, Ill., assignor toTeletype Corporation, Chicago, Ill., a corporation of Delaware originalapplication october zo, 1941, serial No. 415,694. Divided and thisapplication June 30, 1943, Serial No. 492,913

16- claims.

This invention relates tol telegraph systems and more particularly tostart-stop telegraph systems.

This application is a division of application Serial No. 415,694, filedOctober 20, 1941. Systems comprising telegraph codes having uniformnumbers of unit impulses are widely employed for the controlandoperation of various telegraph apparatus such as printers, keyboardmechanisms, and the like. One such code system which is often employedis known as the Baudot five-unit code and aiords thirty-two basicpermutative possibilities. It is often necessary that the selectiverequirements exceed the thirty-two basic selective possibilitiesvafforded in the veunit code, and when such need occurs it is possibleto increase the number of selective possibilities by adding shift andunshiftA code signals. In this way it is possible, despite the fact thatthe available basic signaling possibilities are now reduced to thirty innumber, to increase the total number of signaling possibilities,including said shift and unshift signals, to sixty-four.

It sometimes is desirable to have more than two shift codecharacteristics.V It is possible to `add extra shift and unshif't codesignals, but when this is done the number of` signaling possibilitiesare reduced in number in the original code.- Thus, lit is desirable tobe able to cause'a' shift or unshift condition lto occur While retainingthe thirty-two basic permutative possibilities.

Accordingly, the object of this invention is.t leinlarge the range ofselective possibilities in start-stop telegraph` systems withoutincreasing the number of component vimpulses from that of conventionalsignals. l The systems as described hereinafter are illustrated inconjunction with a type wheel printer wherein itis possible to controlselectively the shifting of a type wheel to any one of four desiredpositions. In general, the system which comprises the present inventionis a system of responsive relay elements made to condition a receiverrelease magnet so as to be alternatively actuable to impulses of twovdifferent electrical characteristics, but in each case to such acharacteristic as is opposed to ythat of the final impulsel of apreceding signal. In this way the nature of the nal impulse of a signalmay be varied and thereby enter into the code combination of itsassociated signal as a permutation impulse. Also, as this impulse servesasa stop impulse no matter what its electrical nature happens to be, theneed for a separate stop impulse is obviated. The systems disclosedhereinafter are described as being responsive to a per- Vforated tape,but obviously, any suitable signal originating means could be used.

For a more comprehensiveunderstanding of the present invention referencemaybe had to the accompanying drawings and to the detailed specicationfollowing hereinafter in which,` similar reference characters indicatecorresponding parts throughout, and in which: j W 1 Fig. Il is aschematic diagram of a System illustrating the invention, whichvutilizes positive, negative, and :no-currentfor signal composition withthe marking impulsestherein varying between positive and negativecurrent characteristics for the purpose of obtaininga shift control;

Fig. 2 is a fragmentary plan section of va modi- Y iication of theinvention;

Fig. V3 is a diagrammatic view of the selector mechanism Ashown in Fig.2 as connected with the mechanism for altering the position of the typewheel;

`Fig. 4 is a schematic diagram of a system which uses an apparatus ofthe4 type ,shown in, Fig. l2 in which the signals are of conventionallength but in which a sixth impulse is incorporated with a stop intervaland theV start impulse is varied to, contrast with the stopv impulse;and Fig. 5 is a diagrammaticchartof a code4 signal such as may be usedin the system disclosed in Figs. 2, 3, and 4 showing how its componentparts are functicnallyallocated. i It is believed that a brief -andgeneral discus- 'sion of the control means ,for selecting thel typewheel position is all that is necessary in the `present disclosure, asthis has been fully ex'- plained and illustrated in ,the` previouslymentioned copending application of which this is a division. I y

Referring to Fig.` l, a type -wheel designated generallyby the numeralII is shown as having four annular rows of vtype pallets I2 thereon.`The type wheel Il isfsecured upon arotatable vshaft I3, so that theproper type pallet `which has been selectedwill be advanced to aposition vadjacent .a printing platen (not shown) against which theselected character is operated to effect printing.. The desired row oftype pallets is presented before the platen by means of a change invertical position of the type wheel VI I. This is accomplished by givingvertical movement to the type wheel II by means of a .bracket I4, whichembraces the shaft I3 ,below a supporting collar I6. Vertical movementof the bracket L4 is possible, according to the position of members I1and I8 with respect Ito shoulders ISand .2.I which form a part of arecess 22 within the bracket. The various positions of the two membersand the resulting position of the type Wheel II is clearly explained inthe above-mentioned copending application.

For the present it is sufficient to say that the member l1 is under theselective control of shift and unshift`v code signals which, through thestart-stop.v selecting mechanism cfvv the printer, position member I1. Amore complete description of this operation may be had by referring tothe previously mentioned copending application, Serial No. 415,694, ofwhich the presentv application is a division. The positiono-f member I8is determined mechanically bymeansof they system which incorporates thepresent invention. 'Ihe mechanical means which causes the bracket I4 tobe moved in a vertical direction is clearly explained in theafore-mentioned copending application of which this is a division.

Preferred system cordingly, to make available for signal transmissionboth. positive and negative current potentiali either one of which is,to be used permutatively with no-current to produce five-unit Baudetpermutation code signals, but Whether the marking signals areconstituted of positive current or of negative current Will determinethealternative characteristic of the secondary shift control.

In the diagrammatic representation, Fig. 1, the reference `character 30'denotes a transmitting distributor of the rotary type which may becontrolled by start-stop or multiplex (synchronous) supervision. A tapesensing unit generally indicated@ 3`I,. is provided with six tape holefeelers. Five ofl them are committed to the five-unit signal code, andtheir contactors 32 are therefore associated Withthe ve segments of thetransmitting distributor 39, but a sixth one Whose contactor isindicated 33', isA designed to sense the presence or absence of a sixthperforation in a six-hole tape', and serves to introducepositive ornegative current to the contact segment 34Which, inturn, introducescorresponding current condition to the marking signals, as Will now be ydescribed;

The tape transmitting apparatus 3Iv may be of anyconventional type, oneembodiment' being illustrate'd in S. Patent'N'o; 1,661,012, except thatinstead of providing'but five sensing levers and associated electricalcontacting apparatus, unit 3'I` may' correspond in all respects theretoso far as th'e conventional feelers levers 32 are concerned', specialfeeler' 33 being simply an additional member and having an additionalpair of contacts With separate contacting points represented by therectangles 36 and 31. The cable contains five lines, eachY connectingone of the feeler lever contactors 32 with its. associated segment in4distributor ring 39. A conductor 4I' con- -nects special feelercontactor 33 with one terminal'oflthe Winding of a polar relay 42.Continuing from the other terminal vof polar 'relay 42 It is to be notedthat the aiore-mentioned segment 34 aligns with and corresponds to thedistributor cyclic period coincident with the conventional start segment48 of distributor ring 39 and that this cyclic interval is in advance ofthe first one of the ve permutation code segments of ring 39. For thisreason, it ywill be observed, theV operation of relay'42'wil1. occur inadvance of the time that brushes 49 encounter said permutation codesegments of ring 39. Thus, the transfer operation on the part of relay42 is made to occur during a no-current interval of the conductor 5I-(segment 48 having no connection-withany of the feelers) and there is inthis Way prevented'the possibility of foreshortened or clipped impulses,a result which might not be avoided'savethrough the utilization of aneutral interval during which to exercise the current reversal.

The normal position of the tape feelers and their associated contacts 32and, 33 may be supposedin the manner illustrated in Fig. 1; that is,with their contacts engaging terminal blocks 52 and 36. Accordingly,when presented against the surface of the tape, said contacts 32 and 33seek to engage the contact blocks 53 and 31, those encounteringperforations beingpermitted to do so and accordingly connecting theirrespective segments of' ring 39 with block 53 which, in turn, receivescurrent potential over a conductor 54, contactor 56, from one or theother of a pair of opposite current sources- 51 and 58. Those notencountering such perforations, however, will, duringthe criticalportion of the signal transfer, fail to obtain current inasmuch as theyWill remain in engagement with the terminal block 52 and hence cause tobe conditioned their respective segments of ring` 391Without electricalpotential or withfno-current.

Relay 42 being of thepolar type, its armature 56- Will move tothe'rightV or to the left engaging the contact points 51 or 58 in.accordance with the nature of current` coming over conductor 4| fromcontactor 33 which may" engage positive current. block 31 or negativecurrent block 36. When placed ineitherl of its positions, armature 56`remains there'until' altered by an oppositepolarity introduced into thelwindings of its relays 42,v Accordingly, it will' be understood' thatthe presence or absence of a sixth perforation will correspondinglyimpress block 53 with positive or negative current and that on thisaccount, permutation code signals generatedover the segments of ring 39may be either positive and nocurrent or negative and nc-current and thatthey will accordingly be so issued out over line conductor 5I.

At the receiving station, there isy connected to line conductor 5I, inseries, the selector magnet 59 and: a receiving polar relay 6I whosearmature 62 will engage or Withdraw'from its contact point 63, dependingupon Whether the marking impulses of the received` signals are ofpositive or negative polarity. In accordancewith the movements ofarmature 62, operating current will be introduced to or withheld fromthe winding of a secondary shift control magnet 64, Vover an obviouscircuit, Fig. 1.

A bell crank armature 66 pivoted at 61 and responsive to theenergization or nonenergization of magnet 64 actuates an intermediatebell crank lever 68. The bell crank lever 68 engages a projection 69integral with the horizontally shiftable member I8. Thus, member I8 maybepositoned with respect to the shoulders I9 and 2|, depending on thecharacter to be printed.`

Since the operation of secondary shift control magnet 64 by the currentcharacteristics as aforedescribed need not be established except duringany one impulse of a signal, and since the most favorable opportunityfor executing the performance (energization or release) of said magnet64 is coincident with `the stop (R) impulse interval, means have beenprovided for shunting the supervisory polar relay BI so that it may notfluctuate except during the precise interval coincident with the stopsignal impulse. This supervision is exercised by a special cam carriedupon a distributor shaft which, acting through a follower lever 12,causes the contact pair 13 to come ajar during the distributive intervalcoincident with the stop impulse, thereby removing the shunt ground froma local circuit, cutting into circuit relay '6| together with selectormagnet 59 and permitting both members to respond to the stop impulse. Atall other times in the distributive cycle, however, the apex of said camof the distributor shaft '|I is withdrawn from the follower leverpermitting contact pair 13 to engage and to thereby effectively shuntrelay 6| out of the signal responsive circuit.

It is to be understood, therefore, that the showing of Fig. 1illustrates a manner of controlling the functioning of a secondary shiftcontrol structune under the supervision of a five-unit code. A shiftcharacteristic for the purpose of supervising a secondary type wheelshift function has been embodied into the standard five-unit code byalternating the currentcharacteristic of the marking impulses betweenplus and minus, the spacing impulses being in all cases no-current.

Modified system In Figs. 2, 3, and 4, there is illustrated a secondsystem of printer control and line transmission for utilizing thefive-unit Baudot code signal in such a manner that it will aord six-unitsignaling possibilities. Other manners of accomplishing this result havealready been disclosed in connection with the embodiments describedabove, as by providing means for supplying two current conditions forthe marking impulses.

In the manner of signaling contemplated in connection with the presentembodiment, there is employed a five-unit Baudot type code combinationsignal having, in addition to the conventional ve selective impulses, aspecial impulse utilized for supervising secondary shift control and astart impulse interval of a polarity opposite to that of its precedingor special impulse interval, under the specific contemplation of thelive-unit code combination impulse interval.

In other words, whereas conventional five-unit permutation code signalsbeing provided with seven componential impulse intervals contemplatestart and stop impulses of predetermined and invariable linecharacteristics, means are herewith provided for varying thecharacteristic of the stop signal interval so that in accordance withthe electrical nature it may have utility for determining vcaseselection as well as for phasing supervision by making the startinitiating apparatus responsive to a start impulse condition oielectrical polarity opposite to that of the immediately preceding stopimpulse interval which, as has been said, may consist of either one oftwo alternative line conditions.

In the incorporation of this plan of operation, it has been foundexpedient to utilize positive and generally indicated by the referencecharacter 8|.

Sensing mechanism 8| is illustrated as having seven contactors 82 to 88,inclusive; however, contactors 81 and 88 both are carried upon a singlefeeler lever while each of theremaining contactors 82 to 86, inclusive,is carried individuallyupon a feeler lever.

In accordance with the operation of its feeler lever, each contactor isspring urged so that it will engage the contact. block towards the rightand is capable of movement in an opposite direction so as to engage thecontact block towards the left, as illustrated in Fig. 4. The contactblock at the right is comprised of a large section indicated 89 and asmaller section insulated therefrom indicated 9|. The contact block atthe left is similarly comprised of two sections, the larger oneindicated 92 and the smaller one 93. Moreover, as may be noted the smallcontact'block 93 is connected electrically over an obvious conductorwith the large contact block-89 and correspondingly small contact block9| is connected electrically with the large contact block 92. Oppositesources of grounded potential indicated 94 and 96 are connectedrespectively to the contact blocks 93 and 9| yand over conductors 91 and98 tothe oppositely placed contact points of armature 99 under thecontrol of a polar relay |00.

The winding of said relay |00 is connected at one end to theafore-described feeler contactor 88 and at its other end to adistributor segment |02 situated in distributor ring |03. Thisdistributor |04 which includes also distributor rings |06, |0'|` and"|08 is of the start-stop type having a brush carrier |09 which supportsvtwo pairs of bridging wipers and I2. Brush carrier |09 of transmittingdistributor |04 is conventionally illustrated in Fig. 4, but it is to beunderstood that this element is driven through a friction couplingpreferably in a rotary direction and that it may be restrained-frommovement by the intervention of an armature I3 under the supervision ofstart magnet I4. Also, that the pair of wipers serve to connectsegmented distributor ring |06 with the solid distributor ring |01 whichis electrically connected to line conductor IIB, and that the pair ofwipers H2 correspondingly connect distributor ring |03 which containsthe segment |02 afore-described with the grounded distributor ring |08.

Attention will now be given to distributor ring |06 which, as may beobserved in Fig. 4, is made up of seven segments. When the brush carrier|09 is in its arrested position, wiper is contacting the slightly longerusegment designated 5 in the distributor ring |06. Also, it may beobserved that following the segment 5 which serves also in the capacityof a stop segment as will later be described, there is encountered astar-t segment designated by the character S.

Following this segment is one designated 0 (zero), which has beenarbitrarily assigned to the functions in a dual capacity, serve. todistribute those signal impulses which relate to the composition of thepermutation code. Segment is connected over a conductor H1 to thefeeler'` 81. Segment S is connected over a conductor H8 to the armature99 of polar relay |00. Fig. 4 illustrates diagrammatically transmittingstation equipment including a perforated tape controlled mechanism and arotary signal transmitter under the supervision thereof for issuingsignals of a type adapted to exercise the control function includingprimary and secondary shift supervision for printing apparatus havingmechanically'the characteristics exemplified in the showing of Figs. 2and 3.

As the brush carrier |019 proceeds in the downward direction asindicated by the arrow H9, the pair of wipers leave segment No. 5 andencounter segment S bridging this element of distributor ring |08 Withthe solid line ring |01.

` Assuming, for the sake of illustration, that the perforated tapesignal which has just been positioned and which has been impressed uponthe feeler levers of record reader 8| is such that contactors 81 and 88(which operate in unison) are moved to the right, that is to say, withcontactor 81 engaging block 89 -and contactor 88 engaging block 9|,distributor segment No. 5 will have received positive current potentialfrom grounded battery 94 over conductor H1. This circuit is traceablefrom positive battery 94, segment 93 to segment 89, feeler 81, conductorH1, segment No. 5 of distributor ring |08, brushes |H to outf goinglineiring |01 which is grounded at the receiving station. As the brushesproceed to the next segment which is designated S, opposite polarity isissued from grounded battery 96 if polar relay |00, in accordance withits preceding operation, has been left in a position whereat itsarmature 99 engaged the contactor of conductor 98. This circuit istraceable from negative battery 96, conductor 98, armature 99, conductorH8, segment S of distributor ring |08, brushes I l to line ring- |01.

If instead of the supposed example described above, the particularsignal had been one in which the feeler lever with which contactors 81`and 88 are integrally associated was positioned to the left causingengagement with contact block 92 and 93 instead of contact block 89 and9|, the electrical characteristics` relative to segments 5 and S wouldbe opposite to that just described. With the brushes passing oversegment 5 negative potential would be supplied from grounded battery 96,segment 9|, segment 92, feeler 8.1, over conductor ||1 to segment No. 5.Likewise, positive current would be supplied from grounded battery 9.1i,conductor 91, armature 99 of polar relay |00, which has been energizedto its opposite position, conductor H8 to segment S of distributor ringl 08. Each of the feeler contactors 82 to 86, inclusive, is connectedover an individual conductor with an associated segment 0 (zero) to 4 ofthe transmitting distributor ring |06. Accordingly, when ja feeler leverencounters a perforated position in the tape, its contactor v will bemoved into one position, say the righth-and one, engaging the contactblock 89l while v forated signal components is, arbitrary,and itv is tobe understood that the reverse association is equally feasible.

The foregoing is true not only of the conventional ve feeler levers ofcontactors 82 to 88, inclusive, but also of the special feeler leverwith which are associated two contactors 81 and 88, as has already beenmentioned. One signicant difference, however, does prevailwhich will nowbe noted. In the case of the special or sixth feeler lever, when aperforation is encountered and, say both contactors are moved to theright, contactor 88 will be introducing negative current from batterysource 98 to the winding of bias polar relay |08 while contactor 81 willbe introducing positive battery from source 94 over conductor H1 to thestop segment 5. Conversely, with the contactors 81 and 88 in theopposite position, that is, engaging contact bloc-ks 92 and 93, positivecurrent originating from source will be introduced throughfeeler 88 tothe winding of bias polar relay |00, while negative current originatingfrom source 96 will be introduced over conductor H1 to stop segment 5.Accordingly, since armature 99 of relay |00 is connected to the startsegment S, the result of the operation of the sixth or special feelerlever will be understood as one controlling the reversal of potentialfor'start segment S, that is to say, with a given condition on the partof segment 5 which may be either positive or negative the sixth feelerlever controlling contactors 81 and 88 operate to provide an oppositecurrent potential to the start segment S.

The purpose in having provided polar relay |00 with its armature 99connecting positive or negative current to the segment S instead ofdrectly connecting the contactor 88 to said segment S` is one ofpermitting the start impulse signal interval to be stored. Thetransmitter utilized is of the well-known magnet type wherein a newsignal is sensed during the start interval. If a new signal should besensed which would cause the feelers 81 and 88 to move to their oppositeposition the start impulse would be of the same polarity as the stopimpulse. However, by providing the polar relay |00, the armature 99 willbe held in a position whereby potential opposite to that of the stopsegment 5 will be assured, as the armature 99 retains such positionuntil the brushes H have passed the start segment S, or until brushes I|2 sweep across segment |02 of ring |03, thus providing a groundedcircuit for the polar relay |00. At this time the armature 99 may moveto the opposite side if the feelers 81 and 88 have moved, but the startimpulse has already been transmitted.

In Fig.v 4, the reference character |2| designates a receiving stationand within said outline are contained the symbols representing vitalapparatus responsive to the signals generated by the transmittingdistributor |04. Of these, the reference character |22 denotes a biaspolar relay whose armature |23 is grounded, and is adapted toreciprocate between two contact points |24 and |28 which are part of alocal circuit for supervising the operation of principal control magnets|21, see also Fig. 2. Y

Also situated in said receiving station local circuit are a pair ofcontactors indicated |28 and |29. The former reciprocates between a pairof contact points |3| and |32 and the latter between a pair of contactpoints |33 and |34. In the printer apparatus which is shown inmechanicall detail in Fig. 2, contactor |28 and its associated contactpoi-nts I3| and |32 are indicated as an assemblyV controlled by afollower arm |36 pivoted at |31 and supervised by a cam apex'l38 whichis one of an assembly carried upon a distributor cam shaft |39. Theshaft |39 may be driven by any well-known means (not shown). Alsocarried on shaftV |39 as an integral part of the afore-mentioned camassembly and in addition to the afore-described cam 'having the apex |38are iive selector signal cams whose apices actuate the ve bell cranklevers |4| mounted in pivotal alignment upon shaft |31 and henceaffording visibility only to the foremost ones in Fig. 2.

A' sixth @am similar to said nve distributorcams isutilized for thepurpose of controlling a storage lever |42, also shown in Fig. 3, whichactuates a bell crank |43 for the purpose of obtaining the referred tosecondary shiftcontrol. In addition to the cams already designated inthe assembly-carried by shaft |39is one indicated |44 having a pluralityof spaced apices, which when said cam assemblyis rotating, serve to rockan armature bell crank |46 about its pivot |41 for the purpose ofpresenting its magnetically attractive arm |48 against the pole face ofmagnet |21. This operation of cam |44 in assisting the armature |46 andthereby diminishing the work of magnet |21 is in accordance withrecognized practicein printing telegraphy.

As illustrated in Fig. 2, storage lever |42 is disposed below the otherstorage levers |49 and |5|. This arrangement is in a general sensearbitrary, since the shift signal impulse, in the particular instancecorresponding tothe segment l] on the distributor ring |06, Fig. 4, maybe located if preferredin any other position with respect to thecomponential sequence both 'in distributor ring |85 as well as in thestack of selector storage levers, Fig. 2, designated |42, |49, and |5|.Storage levers |5| are iive in number corresponding to the signalcomponents which utilize the segments 2, 3, 4, and 5 in the transmittingdistributor ring |06. Storage lever |49, together with the top one oflevers |5|, correspond to the code signal impulse occupied by thesegment 5, and in the order designated each impulse ultimately serves toplace its associated lever |49 or |5| in one or another of its twopossible positions, against pin |52 or pin |53.

For the purpose of understanding the principles of the instantimprovement, it will suffice to state that ultimately the storage signalis manifest by a conditioning of the several storage levers |42, |49,and v|5| with the lever I 42 exercising the function of controllingsecondary case shift bell crank |43 and levers |5| functioning tocondition the setting of code discs |54 which are five in number.

Storage lever |49 controls the shifting of abovementioned contactor |29.Accordingly, when it is found in the position as illustrated in Fig. 2,it permits contactor |29 to engage its upper contact |33, and when it isin an opposite condition such as that occupied by the counterclockwiseextreme storage lever |5|, in Fig 2, said lever |49 by its protuberance55 will engage the insulated extremity of contactor |29 and thrust thelatter tension to recede from contact point |3| and to engage insteadcontact point |32. l. There will now be described the eiect of thesupervision of conis, the current characteristic which will `positionits sword |62 in the manner opposite to that ndcated in Fig. 2 so as toplace storage leverI |49 polar relay |22'to cause it to move itsarmature |23 to engage contact point |26 so as to close the circuit forselector magnet |21 and to causethe armature lever |58, Fig. 2, toassume its `marking position. Subsequently, there will follow the startsignal impulse whose eiect upon relay |22 will be opposite to that justdescribed in connection with the N o. 5 signal impulse, which reversalis assured by the apparatus of the transmitting distributor describedabove. In consequence, relay armature |23 will be moved clockwise toengage its contact point |24, opening the circuit for energizingselector magnet |21 and thereby releasing the selector apparatusV for agiven cycle.

Under the alternative condition of operation, that is, with the No. 5impulse being of spacing nature, contactor |29 will be withdrawn fromcontact point |34 and thrust into engagement with contact point |33instead. Cam shaft l |39 carries in addition to the afore-describedoperating cams |38 and |44, a spiral distribution of cam apicesindicated |59, five in number. Each one of these is related to one ofthe signal impulses '1 to 5, inclusive, whose corresponding segmentsappear in the distributor ring |06, Fig. 4, while the nal one of saidseries designated |5|, Fig. 2, Yis, in accordance with the presentembodiment, of double width. i

This is so because unlike the other of the cams |59 Lwhich serve toactuate but a single one of the claw levers |4l, it alone actuates apair of said claw levers |4 namely, the claw lever which actuates thesword |51 identied with the No.5

impulse interval and the sword |52 which controls contactor 29. This isso because said sword `|51 controls its associated code `disc and sword|62 must substantially concurrently condition contactor |29 through thelever |49. Since said levers |4| are all of the same contour, they maynot be differentiated in the showing of Fig. 2, however, on account ofthe spiral arrangement of said cams |59, each claw lever |4| will beoperated ata particular `cyclic interval, except said two claw levers|4| which are operated in unison by the special apex |6|. Each clawlever is provided with a sword |51 but the sword which is associatedwith the anterior lever |4|,I as viewed in Fig. 2, has been speciallydesignated |62. Each sword |51 and |62 terminates with ablunt pointprojection which rests against one side or the other of a hump |63 of anintermediate lever elemerit, iive vof which are, designated |5| but theone related to the sword `|62 ofwhich 'is designated |49. The fivesimilar levers each are provided with a tail piece |64 that serves as alocking projection by being placed on one sideor .the other of a lockingbail |66, which member assumes the positio'n indicated in Fig. 2,Vexcept during-a brief interval following the conclusion ora-particularsignal when its lever arm |61 is released by the operation of anauxiliary shaft, notshown.

"Accordingly, while the several swords |51 and |62'may assume oneposition or the other as its abutment |68 or |69 encounters thedownwardly extending vane |1| or |12 of armature lever |58, levers- |49and |5| may not be correspondingly lpositioned until said swords |51 and|62 are thrust downwardly by the clockwise movement of the claw levers|4|, which movement is urged by their individual springs |13` as well asby auxiliaryindividual springs carried upon an integral extension oflever arm |61.

'The auxiliary springs of lever arm |4l are not 'shown iny Fig. 2 of theaccompanying drawings, vbut Areference may be had to the aforedescribedcopending application where it is explained that their function is of anauxiliary nature and to assist the principal actuating spfrirl'gsl131'ANone of the springs |13 or the aux iliary springs mentioned may actuatetheir associated claw levers |4| during the time that the locking bail|66 'intervenes by blocking the extending portions |64 of Vlevers |5I.However, since lever |49 is'not provided with an extension |64 asare'the remaining ones of the levers designated `.|5'|, its response toits associated sword |62 will occur immediately following the instantwhen cam apex |6| passes the follower projection of claw lever |4l whichcarries said sword |62;

"Thus, ywhile the consummation of a signal transfer relating to aparticular set of 4code impulses of any signal must awaita briefinterval folldwingthe fifth or stop code impulse, the actuationof'co'ntactor |29 by the projection |56 of special storage lever I49follows immediately upon receiptof the fth code impulse. This assuresthe 'operation of selector magnet |21 for the purpose V'of arresting therotation of shaft |39 co- 'incidentally with the signal intervalcorresponding t the stop or fth code combination impulse,

. even though the other purpose ofthe particular impulse, namely, thatof setting one of the code discsv |54, may await its regular period ofoperation which, as has been said, occurs after the lapse of a brieftime interval and, in fact, during the occurrence Yof a succeeding codecombination signal.

' Cam apex |38 is specially provided for the purpose of actuating theaforo-described arm |36 which, in turn, controls contactor |28. Cam

apex |36 isr eiective to thrust contactor |28 against Vits contact point|3| for a period commensurate approximately with the beginning of thestop or No. 5 code combination impulse and continuing through the startimpulse S and to the Q (zero) or shift controlling impulse. At othertimes, contactor |26, see also Fig. 4, engages its contact point |32 fora purposev which will'now be described.

Operation of the modifiedA system "Concisely stated, armature |23 ofrelay |22 liuctuates, in accordance 'with each signal impulse, contactor|28 being'controlled by cam apex |38 rests against contact point |32 atall times except during the stop and start signal interval, and cotactor|29 being controlled by the No. 5 or stop signal is moved into one orthe other of two alternative positions as a result of the operation ofthe transfer mechanism, described above, only during the periodcorresponding to this impulse. Under an assumed set of conditions, inresponse to marking signals, both armature |23 and contactor |29 will bedeflected downwardly, that is, to engage their contact points |26 and|34, while under spacing signal impulses, said armature and contactorwill be in theirfopposite position, that is, engaging respectively theircontact points |24 and |33. Also, it is to be recalled that sincethe No.5 impulse functions in a dual capacity of effecting the distributor stopcontrol as well as of entering into the permutation code, each cyclemust beconsidered as including a part of the preceding No. 5' impulse,which affects the current characteristic of the start impulse as well asof the concluding No. 5 impulse, because it, together with the impulsesNo. 1, 2, 3, and 4, comprises the code combination of the particularsignal.

Accordingly, when the No. 5 impulse of a preceding signal happens to bemarking, armature |23 will be thrust into engagement with its contactpoint |26, contactor |26 will be thrust into engagement with its contactpoint |3| (on account of the'operation of cam |36) and contactor |29, asa result of the transfer operation, will be moved into engagement withits contact point |34. This will complete a circuit traceable fromgrounded battery at |16, winding of magnet |21, conductor |11, contactor|29, and its contact point |34 with which it is then in engagement,conductor |18, contact point |26, and its armature |23 which is then inengagement with it, to ground. As a result of the continued energizationof magnet |21, its armature is held and the rotation of shaft |39 isarrested in accordance with the conventional operation of printingtelegraph selector shafts. This condition continues until the circuitfor energizing magnet |21 is broken, which change occurs upon thereceipt of a proper start impulse over segment S of transmittingdistributor ring |06. rThe polarity of the start signal being oppositeto that of the No. 5 or stop signal impulse, as already explainedycauses armature |23 to be moved to engage its contact point |24 and awayfrom its Contact point |26. This interrupts oropens the circuit formagnet |21, causing the release of its armature |48 and consequentlyinitiating the rotation of receiving distributor shaft |39 in a mannerclearly described in the copending application referred to. l

As distributor shaft |39 rotates, cam apex |38 rides, off the projectionof arm |36 permitting contactor |28 to be drawn away from its contactpoint 3| and to come into engagement instead withv its contact point|32, meanwhile contactor v|29 remaining in engagement with its contact.point |34 because it can be changed only during the occurrence of thefifth impulse. As a result of the change in contactor |28 from contactpoint |3| to contact-.point |32, no eiect is obtainedat this time,magnet |21 continuing to be de-energized untilduring the course of thesucceeding six signal impulses, 0 1, 2, 3, etc., armature |23 inresponse to its relay |22 returns to engage its contact point |26, whichresponse can occur only under the. control of marking signal impulses. nIn the event thatr ainarking impulse isl received during the 0V (Azero)impulseinterval, the action of one of the swords |51 upon the storagelever |42 will cause bell crank 14S-to b rotatedclockwise, in aV mannerand for a purpose to be described later.l In the event marking impulsesare received for any. of the other impulse intervals 1 to 5, inclusive,their storage levers |49 and will 'be accordingly positioned, causingcorresponding placement of the several code selector discs |54 aftertheselection has been completed and the transfer mechanism operated, but ofparticular significance in this connection kwill he .the currentcharacteristic of the No. 5 signal impulse. If this signal impulse isagain marking in nature, the succeeding operation will be the same asthe one 4just described except for the variations which may occur in thecode combination, but if instead the signal impulse corresponding tothe` No. 5 interval happens to be of spacing nature, then armature |23will respond by engaging its upper contact point |24 and sword |62 willbe disposed in the manner illustrated in FigfZ. l As a result of thelatter incident, contactor |29 will be permitted to engage its uppercontact point |33 instead of the lower contact point |34, while onaccount of cam apex |38, contactor |28 will again be thrust against`contact point |3|. Thus, a circuit will be completed for energizing themagnet |21traceable from grounded battery |16, through the winding ofmagnet |21, conductor |11, contactor |29 which is then in engagementwith its contact point |33, conductor |19, contactor 28 and its contactpoint |3|, conductor |=8|, contact point |24 and armature |23 which isthen in engagement with it, to ground.

As a result, magnet |21 is held energized which is-the proper conditioncorresponding to a stop impulse until an opposite current condition isreceived by relay |22 causing its armature |23 to be withdrawn fromcontact point |24 vand to engage instead Contact point |26. When thisoccurs, contactor |28 is still held in engagement with its contact point|3| because of the described function of cam |38, which maintains saidcondition until after the interval corresponding to the start, S,impulse. Meanwhile, the last described movement of armature |23 causesthe energizing circuit for magnet |21 to be'broken .and accordinglyreleasing its armature |48 for the purpose of initiating rotation ofreceiving distributor shaft |39, as afore-described.

Thereafter and coincident with the`0 (zero) signal interval, apex of cam|38 restores contactor |28 to its condition prevalent during the majorportion of the cycle; that is, engaging its contact point |32. When thisoccurs, that is, when armature |23 of relay |22 engages contact point|26, marking impulses are thereafter interpreted as magnet .|21energizing impulses, because contactor |29 continues in engagement withits contact point |33, causing the magnet |21 energizing circuit to becompleted over the following described course. The current originateswith grounded battery |16 through the winding of magnet |21, conductor|11, contactor |29, and its contact point |33, conductor |19, contactor|28 and its contact point |32, conductor |18, contact |26 and armature|23, to ground. Thus, phasing of the receiving magnet |21 as Well as ofits controlled shaft |39 is regulated notwithstanding the reversedcondition' of the No. 5 and start impulses.

Referring now to Fig. 3, it is to be seen that the apparatus as shown inthis figure is very similar to the apparatus shown in Fig. 1, thedifference residing in the manner in which one ofthe' memberswhichcontrols the vertical movement of the type wheel is positioned. It isbe- A lieved that a description ofthe operation may be given in whichnumerals similar to those used in the description of Fig. 1 are used, asfar as is possible. When the sword |51 identified with the zero impulseinterval is positioned in response to a spacing signal so as to engagestorage lever |42 on the left side, that is, to the left of the pivotpointof the lever, the lever |42 willbe pivoted in a counterclockwisemanner. Any counterclockwise movement of storage lever |42 causes anengagement and subsequent movement of bell crank lever-` |43 in aclockwise manner,

about its pivot point. The end of bell crank larm |43 will engage thedepending lug |86 of member |81, causing member |81 to move to theright, as viewed in Fig. 3. Any movement of fthe member |81 positionsitand its lug I8 with respect to the shoulders, as previously described inthe description of Fig. l. Depending upon the position of lug |8 withrespect to the shoulders i9 and 2|, the type wheel Il will be positionedvertically so as to present the line of type pallets l2 which it isdesired to print againstV the adjacent platenrnot shown). Member |81 isreturned to its leftward position by means of a spring which is notshown in Fig. 3. This return occurs when the sword |51 is moved to theright of the pivot point of storage lever |42, as seen in Fig. 3. Thepressure being removed from bell crank arm |43, the above-mentionedspring is strong enough to return member |81, overcoming any resistancewhich might be exerted by bell crank arm |43. It is not believed that afurther discussion of the apparatus and its operation is necessary assuch a discussion has been given with respect to Fig. 1.

While the foregoing electrical systems have been described as for acertain purpose and with the use of specific apparatus, it is to beunderl stood that these'systems could be used for other `purposes andwith apparatus other than that described. Accordingly, the invention isnot intended to be restricted in any manner to the language of thedetailed specification or to the illustration in the accompanyingdrawings, except as indicated in the hereunto appended claims.

What is claimed is:

` 1. In a start-stop recording apparatus, a selector magnet, meansresponsive to line signals comprised of a xed number of permutation codeimpulses and a xed number of phase regulating impulses, each of saidimpulses being of alternative electrical characteristics for accordinglyenergizing or de-energizing said magnet, circuit conditioning means forrendering said magnet variably' responsive to said code combinationimpulses, and additional means for preparing said magnet to respondinvariably in accordance with said phase regulating impulses.

2. In combination, telegraph selecting apparatus, a receivingdistributor having cyclic operation, means responsive to a pair ofcontrasting signal impulses and independent of their specic nature forregulating the phase of said receiving distributor, and means includinga single selector magnet responsive to the electrical nature of a seriesof impulses at least one of said impulses being one of the phaseimpulses for controlling the selective operation of said apparatus.

3. In telegraph selecting apparatus, a selector mechanism, a singlemagnet for initiating said selector mechanism and for variably operatingit in accordance with linecurrent variation, means responsive duringcertain vvcurrentimpulse 'intervals 'for 'energizing said magnet inresponse to marking current or for 'de-energizing said magnet inresponse to spacing current, and means :effective during'certain impulseintervals only -for energizing vsaid magnet in response to :either 'kindof current and for cie-energizing said magnet in response to succeedingopposite current.

4. In a start-stop recording apparatus, a selec- 'tor magnet, circuitmeans -responsive to line sig- `na'ls comprised of a xed number ofpermutation code impulses and phase regulating impulses 'each oTalternative electrical characteristics, 'means for accordinglyenergizing or desenergizring said magnet, and circuit conditioning meansfor preparing 'said magnet to respond to said `phase regulating impulsesindependent of their 'individualelectrical character.

5. In a telegraph selecting apparatus, a `selector mechanism, a singlemagnet for initiating said selector mechanism and for variably operatingit in accordance with alternative line current variations, and meanseiiective during certain ir'npulse intervals for energizing said magnetin response to `either of said alternative line Vcurrent variations andfor de-energizing said magnet 'in response to a succeeding opposite oneof said Variations. Y '6. In a start-stop Vtelegraph system,transmitting apparatus comprising means for gener'- ating signals of apositive, negative, and nocurrent `characteristic composed Aoi? aconstant number of Apermutation code 'impulses and a "constan't numberof phasing control impulses, receiving apparatus vcomprising a selectormagnet responsive to all impulses of said generated v'signals, and a'shift 'control magnet responsive to lone impulse 'only of saidgenerated signals.

7. In a start-'stop telegraph system, transmit'ting apparatus comprisinga six-unit permutation code sensei', a transmitting distributor forissuing five-'unit code signals comprised of a con- 'stant number ofpermutation code impulses of a positive, negative, or nocurrentcharacteristic, and na phasing control impulse of a positive or negativecharacteristic, the sixth code unit 'determining the electricalcharacteristics of said impulses, receiving apparatus responsive.permutatively to the variations in the characteristic of saidpermutation code impulses to selectively ree cord, and means associatedwith said receiving apparatus responsive to the variati-ons in the4characteristics of said phasing impulse -for the purpseof obtaining ashirt control.

8. In a telegraph system, means to transmit signals each composed ofvarying permutations of positive, negative, and no-current impulses, twomagnets, means to operate one magnet 'according to the current kornoi-current vnature 4Vof the impulses, means to operate the other magnetaccording to the positive or negative nature of the impulses, and meansto make a record 'varying according 'to the operation of 'both magnets.

' `9. In a telegraph system, means to transmit signals each composed ofthe same predeter- 'mined number of positive, negative, rand1ro-'curvrent impulses, two magnets, means to operate one .magnetaccording Tto the current or no-c'urrent nature gf 'th'e impulses, meansto operate the -other magnet :according to the 'positive or negativenature ofthe impulses, means to make Aa record varyingaccording to 'the:operation of both magnets, yand vmeans to start the receiver intooperation under control of 'a particular one of the vpredeterminednumber lof impulses.

' `10. In 'a telegraph system, means to transmit signals 'each composedof-'the same number of elern'erita-1 intervals Vcomprising positive,negative, and 'n'oecurrent impulses, two magnets, means to operate onemagnet according to the vcurrent or no-current nature 'of the impulses,means to operate thefo'ther magnet according to the positive or negativeofthe impulses, and means to make a Irecord varying according to the'operation of porn magnets.

11. In a 'telegraph system, means to transmit signals composed 'ofpositive, negative, 'and nocurrent impulses, two magnets, meanstooperate one magnet perrnutably according to the current or rio-current`nature of the impulses, means 'to operate the other magnet laccordingto the posi-- tive or negative Vnature of the impulses, and "means tomake a record varying according to the 'operation of both magnets.

l2. VIn ya telegraph system, means to transmit signals each composed ofan invariable number of time intervals, tivo magnets, means to con#'trol one magnet during all the time intervals of said signal, and meansto control the other inagnet 'during a single vone time interval of saidsignal.

41'3. In va telegraph system, means to transmit signals composed ofpositive, negative, 'and nocurrent impulses, two magnets, means 'tooperate one magnet according to the current or lrio-current nature ofthe impulseameans to operate the second magnet according to 'thepositive 'or negative nature of the impulses, a shunt circuit to preventthe operation of said second magnet except .at a predetermined time,'and means to make a record Varying 'according 'to the operation of bothmagnets.

i4. In a telegraph system, mea-ns to generate signals composed Vofcurrent Aand nocurrent intervals, means to alter the polarity 'ofsuccessive 'signals during a noecurrent intervalv separating signals,and means to vary the record according t0 Y'the polarity of thecorresponding signal.

l15. In a system of telegraph c(immunication,4

the method Vof operation which vcomprises the steps of transmittingsignals composed of a nxed number of time intervals, transmitting insaid signals various permutations of current and nocu'rrent, varyingthepol'arity of 'the current in dinerent signals, and making a record inaccord-i ance to Vthe .permutations of current and nocurrerit and alsoaccording to the polarity.

i6. In a telegraph system, means to transmit groups or signals, each oisaid groups 'of signals comprising a plurality of impulses, at least one-Oi said impulses assigned to -a,st'op vfunction, meansto vary thecharacter of ysaid stop impulse 4accordingto the character to betransmitted, a recorder, a 'selector shaft -in said recorder, a singleselector magnet operated by all .of said signal impulses, means toarrest said selector ,shaft 'under the control of said selector magnet:at the end of "each, signal group independent of the polarity of saidstop impulse, and means in said recorder to .make Y'a record undercontrol lor" said selector magnet and varying accord-ing to'the'polarity fof said stop impulse.

Louis M. Porre.

